1. Field of the Invention
The present invention is generally related to the operation of grease guns. More particularly, the present invention pertains to a system and method for refilling the reservoir of a grease gun without the need of a secondary pump.
2. Introduction
Grease guns utilize a reservoir, for example, tubes or cartridges, to hold grease while a plunger, pull rod mechanism, or other similar mechanism forces grease from the reservoir to a dispenser. When the gun runs out of grease, the tube in the reservoir is usually replaced. Replacing the reservoir generally means using multiple steps to remove the spent tube or cartridge and replacing it with a new one. Replacing the reservoir also means that one comes into contact with grease residue contained in the old reservoir or grease from the new reservoir resulting in an unwanted mess. Moreover, disposal of the spent reservoir becomes an environmental concern because of the remaining grease residue. Though the grease gun has been improved over the years, grease residue resulting from the process of switching from an old grease reservoir to a new grease reservoir remains an issue. Related U.S. Application No. U.S. application Ser. No. 13/916,569, entitled “Refillable and Rechargeable Grease Gun Reservoir,” describes a refillable and rechargeable grease gun reservoir that eliminates or partially eliminates the prior process of changing grease tubes.
However, even with improved grease gun reservoirs, one still needs a secondary pump to be able to pump refill grease into a grease gun reservoir. Prior grease guns are generally configured to allow grease to flow “one way” from the grease gun reservoir through the grease gun head onto the desired application. To refill the grease gun, either the manual method described above is used or a secondary pump is used to recharge and refill the reservoir. This adds to the amount of equipment needed to service modern grease guns. What is needed is a system and method that eliminates or partially eliminates the need for a secondary pumping mechanism to refill the grease gun.